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Fidel API provides a developer-friendly, secure and reliable API for businesses to link payment cards with mobile and web applications. Through a single API, developers can securely access data from the three major card networks and build their applications on top of the powerful payments infrastructure.

When a consumer makes a purchase at a participating store with a linked card, Fidel API spots that transaction and sends it to your server in real-time through webhooks. 💳⚡️

Fidel API runs on top of global payment networks, so it doesn’t require changes to existing merchant infrastructures. No need for new software, POS integrations, staff training or new cards. All the PCI compliance requirements are managed by us so you don’t have to.

Currently, the API is available in the United States, UK, Ireland, Canada, Sweden, Norway and Finland, with Australia, Japan and South Africa going live soon. Please refer to the up-to-date list of countries and schemes. We work continuously to add support for other countries and networks. If you would like to deploy card-linked applications in other countries please contact us at

Check out the API Reference to see all available requests, code examples and response payloads.

Join our Developer Community for API discussions, documentation, frequently asked questions, roadmap and new features. We’re always happy to help and answer any questions.

Card Linking

The iOS, Android and Web SDKs provide you a secure UI to collect your user’s card details securely on the web or mobile.

By using Fidel SDKs, card details are sent directly to Fidel API through a secure connection without exposing your servers to sensitive information taking care of all PCI compliance requirements.

Your apps will receive an id back that identifies the card in each transaction.

Preview of the web and mobile Fidel card linking UI

Use one of our test card numbers (for example 4444000000004004) and enter an expiry date in the future.

Web SDK integration script


  data-company-name="Your Company"
  data-title="Link Card"
  data-subtitle="Earn 1 point for every £1 spent online or in-store"
  data-delete-instructions="tapping remove in your settings page."
  data-button-title="Link Card">

Check the Web SDK documentation section for more information about all available parameters, customisation options, and the metadata nested object.